Sterilization system

ABSTRACT

A sterilization system preferably utilizing two baths in which articles to be sterilized are immersed into a first bath where the articles are conditioned and then into a second bath containing a sterilizing solution where they are sterilized. The ingredients for the sterilization system are stored in hermetically sealed pouches which are opened just prior to use to release and activate the system. The sterilization system utilizes a chlorine solution which is highly efficacious while being non-corrosive and having a reduced toxicity and prolonged shelf life, and may be utilized by relatively untrained personnel.

This is a division of application Ser. No. 924,018, filed July 12, 1978.

BACKGROUND OF THE INVENTION

Chlorine-based disinfectants have played an important role in medicalhistory. As early as the 18th century, the bleaching and disinfectingproperties of chlorine were recognized. In 1846, the efficacy wasdemonstrated of solutions prepared from chloride of lime for preventionof puerperal fever. Shortly thereafter, calcium hypochlorite was usedfor treating water. World War I prompted investigation of the use ofchlorine solutions for cleansing infected wounds. In 1915, Dakinreported experiments concerning the chlorine solution which bears hisname (Dakin, H.D.: The antiseptic action of hypochlorites, Brit. Med. J.ii:809 Dec. 1915). Subsequently, the results of lavaging foul woundswith Dakin's solution were lauded.

Bacteriological studies in this century investigated vital parameters ofchlorine solutions. Germicidal action depends on the concentration ofhypochlorous acid (Charlton, D. & M. Levine: Germicidal properties ofchlorine compounds, Iowa State College Bulletin 35:48, 1937). Both thequantity of chlorine compounds and the pH of the solution determine theconcentration of hypochlorous acid. The higher the pH of a chlorinatedwater solution, the lower the concentration of undissociatedhypochlorous acid. At pH 7.5 approximately 50% of the chlorineconcentration will exist as undissociated hypochlorous acid (HOCl) whilethe other 50% will be present as hypochlorite ion (OCl) (White, G.C.:Handbook of Chlorination, New York, Van Nostrand Reinhold, 186, 1972).Maximum efficacy of a given concentration of chlorine in solution occursbelow pH 5, when all of the chlorine present exists as undissociatedhypochlorous acid. Bacteriological tests substantiate that, ashypochlorite solutions are acidified, a marked increase in germicicalaction occurs. With pH control, chlorine has proved to be one of themost potent and reliable germicides. As such, it became widely used inwater and sewage treatment.

Early studies elucidated a number of problems with chlorinedisinfectants. Dakin (previously identified) recognized the "highlyirritating character" of some chlorine solutions and learned that tissueirritation could be reduced if both the concentration of hypochloritesand the pH were controlled. Dakin discussed the importance ofneutralizing the solution by adding acid to the alkaline hypochloritecompound. Dakin's "neutralized" solution could be continuously appliedto wounds without serious irritation.

Another problem is that chlorine solutions are very unstable. Theeffectiveness of these solutions deteriorates significantly within a fewhours. This problem depends largely on the pH of the solution. The morealkaline a hypochlorite solution is, the less hypochlorous acid ispresent, the less effective it is as a sterilant, and the more stable itis. An example of such an extremely stable hypochlorite solution isordinary household bleach. The more acid such a hypochlorite solutionis, the greater is its hypochlorous acid content, the more effective itis as a sterilant, and the greater the instability of the solution.Cullen indicated that the lower limit of pH of Dakin's solution wasabout 9, for below that level the solution became too unstable forclinical use (Cullen, G. E. & H. D. Taylor: Relative irritant propertiesof the chlorine groups of antiseptics, J. Exp. Med. 28:681, 1918).Depending on the initial concentration of hypochlorite, the effectivehalf-life of an acid solution may be only a few hours. A trulyneutralized chlorine solution must be mixed immediately prior to use.

The high reactivity of chlorine creates another major problem with itsuse as a sterilant. Early in this century, Carrel recognized asubstantial reduction in the germicidal efficacy of chlorine solutionsto which blood serum had been added and remarked about the rapiddisappearance of hypochlorite in contact with body tissues and fluids(Carrel, A. & G. Dehelly: The treatment of infected wounds, London,Univ. of London Press, 1918). In a more recent study, addition of only300 ppm of lactose, a natural sugar, was found to significantly reducethe efficacy of a chlorine solution (Rudolf, A. S. & M. Levine: Factorsaffecting the germicidal efficacy of hypochlorite solutions, Iowa StateCollege Bulletin, 40:35, 1941). Chlorine readily combines with a widevariety of organic and inorganic substances and is thereby inactivated.Reliable use of chlorine-based germicide requires adequate cleansing ofmaterials to be sterilized to remove such ubiquitous contaminants asprotein or grease. That cleansing must be performed with compatibleagents. Most common cleansing agents are not compatible because theybind and inactivate chlorine compounds.

Chlorine solutions have no inherent wetting or detergent capacity.Therefore, microorganisms which are encased in an air bubble or in oildrop escape destruction. Addition of a surface active or wetting agentto the chlorine solution can increase penetration and contact. Carefulevaluation is required to assure that the agent used is compatible anddoes not bind and inactivate significant amounts of chlorine. Additionof specific compatible detergents to chlorine solutions has beenreported to increase their germicidal efficacy. (Petroff, S. A. & P.Schain: The enhancement of bactericidal properties of well knownantiseptics by addition of detergents, Quart. B. Seaview Hosp. 5:378-379, 1940). Such combinations of chlorine compounds with compatiblesurfactants, though fine germicides, are not now generally used assterilants because of their corrosive character.

The most difficult to solve problem of chlorine-based germicides is thatthey are highly corrosive. Concentrations of hypochlorous acidsufficient to sterilize standard bacteriological challenges also quicklyattack metals, even stainless steel, causing discoloration and pitting.Metal instruments soaked in chlorine solutions tend to be irreversiblydamaged. Sharp edges are destroyed and metal surfaces become pitted anddarkened. Instrument manufacturers have been known to remark that theydislike having a product exposed to a chemical which magnifies anymetallurgical flaw in even the best stainless steel. Corrosioninhibitors have been recommended for use with hypochlorites (Botham, G.H. & G. A. Dummett: Corrosion by commercial sodium hypochlorite and itsinhibition, J. Dairy Res. 16:37, 1949). Sodium silicate was found to beeffective in an alkaline solution containing 150 ppm available chlorine.The increase of alkalinity, however, substantially decreases germicidalefficacy. Sodium silicate insufficiently retards corrosion in moreconcentrated hypochlorite solutions. Many other anticorrosive agents areincompatible because they react with and inactivate chlorine. Resolutionof this problem is required in order to provide a chlorine sterilantwhich is safe for instruments.

Dr. J. C. Kelsey investigated liquid disinfectants for many years. Hedeveloped the "Kelsey-Sykes" test, which is now the British refereebacteriological challenge test. In recent years, Dr. Kelsey recommendedsodium hypochlorite solutions as the most efficacious liquiddisinfectants. He tried to develop an optimal chlorine solution andpublished a report of his work in 1974 (J. Clin. Path. 27, 632-638). Thechlorine solution which he recommends in that article is highly toxicbecause of its methanol content and its unadjusted alkaline pH. It isalso extremely corrosive.

Since Dr. Kelsey retired, Dr. David Coates has carried on the work onhypochlorite solutions. He published a report of his work in 1978 (J.Clin. Path. 31, 148-152). Further experiments indicated that thehypochlorite solutions which he had reported in that publication, weretoo corrosive for routine use. Therefore, to control the corrosive andtissue-irritating properties of the solution, Dr. Coates reduced theconcentrations of alcohol and of available chlorine (to about 200 ppm).He has also learned that buffering the pH of the solution is vital. Thechlorine solution which he has most recently recommended, however,contains neither a satisfactory surfactant nor an anticorrosive agent.

Despite the long history of efficacious use of chlorine compounds asdisinfectants, few chlorine compounds today are used as sterilates inmedical practice. None of the existing solutions meets the requirementsof an optimal chlorine-based sterilizing system. The idealcharacteristics of such a system are the following:

1. It must reliably kill the standard U.S. Government bacteriologicalchallenge (called the "AOAC" test), preferably within a contact time of30 minutes or less. Existing liquid sterilants require contact times ofmany hours to pass the "AOAC" test.

2. It must be completely non-corrosive and non-damaging within therecommended contact time.

3. Its pH must be adjusted to and maintained at approximately neutral inorder to increase efficacy, reduce toxicity, and avoid the rapiddeterioration of potency which occurs in more highly acid chlorinesolutions.

4. It must assure proper preparation of materials to be sterilized, in away which avoids contamination by organic matrial or chemicals whichmight inactivate the chlorine.

5. The system must be so simple that even untrained personnel canprepare and use it without significant error.

In order to maintain the pH of a solution within a desired range,buffers are usually used. One of the most common buffers in the neutralrange contains phosphates. For buffering purposes, less than 1% ofphosphates will suffice. A solution containing 0.2% hypochlorite,buffered at pH 7.5 with phosphates, is an efficacious sterilant. Such asolution, however, is corrosive and has undesirable surface tensioncharacteristics.

Many investigators have used standard concentrations of phosphates tobuffer chlorine solution (e.g. Friberg, L. & E. Hammarstrom: The actionof available chlorine on bacteria and bacterial viruses, Acta. Pathl.Microbiol. Scand., 38:128, 1956). Phosphates are included in lists ofcorrosion inhibitors (Uhlig, H. H: The Corrosion Handbook, NY, Wiley &Sons, 906-7 and 913-14, 1948). Concentrations of phosphates under 1%have been added to chlorine-based disinfectants to reduce corrosion(Diversol BX, Brit. Pat. No. 781,708). However, it has not heretoforebeen known to use concentrations of phosphates over 1% to achievesubstantial corrosion control.

According to the present invention, it has been determined thatconcentrations of phosphates in excess of 1% markedly reduce thecorrosiveness of the solution. The concentration of phosphates necessaryto control corrosion depends on several factors including theconcentration of hypochlorite, the pH, the presence of a surface activeagent, the contact time, and the type of steel. In a solution at pH 7.5containing 0.02% sodium hypochlorite and a compatible surface activeagent, addition of a total of 1.17% phosphates produces a 93% reductionin the corrosion of carbon steel during 4 hours contact. In a similarsolution containing 0.2% sodium hypochlorite, addition of a total of2.75% phosphates produced a 97% reduction in the corrosion of carbonsteel during 2 hours contact. When the concentration of total phosphatesin the latter solution was increased to approximately 7%, no notablecorrosion of common steel occurred. In this instance, even 24 hours ofsoaking of common steel produced no visible change.

The combination of phosphates in the solution acts as a buffer,resisting alteration in the pH. The concentrations of acid and alkalinephosphates are adjusted to produce approximate neutrality. Under thiscircumstance, a solution containing as high a hypochlorite concentrationas 0.2% exhibits little tendency to tissue irritation. When thatsolution is repeatedly dropped into the eyes or rabbits, according todirections for the Draize test, no evidence of inflammation occurs (seeExample IX).

According to the present invention a surface active agent is included inthe chlorine solution. Air bubbles on material not only preventsterilization but also promote corrosion. The addition of a detergentreduces surface tension and helps avoid formation of bubbles. Fewdetergents, however, are compatible with both chlorine and phosphatesand also effective at ph 7.5. Some effective surfactants which do notreact with chlorine, for example, combine with the phosphates causingprecipitation. A nonionic agent which meets the desired requirements isa 12 carbon alkyldimethyl amine oxide, for example, dimethyl laurylamine oxide (see U.S. Pat. No. 3,296,145). This amine oxide is availableunder the following trademarks: Ammonyx LO and Barlox 12.

The addition of this amine oxide to the sterilizing system of thepresent invention increases the efficacy of the solution. Suture loopsplaced on the surface of a buffered chlorine solution lacking detergentwill float. If the loops are forced under the surface, many tiny bubblesare visible on their surfaces. When a solution contains an adequatesurfactant, the loops rapidly sink into the solution without visiblebubbles. With the addition of the amine oxide, solutions of the presentinventon exhibit adequate surface tension characteristics (see ExampleVIII).

Inclusion of the surfactant in the sterilizing system of the presentinvention also measurably enhances corrosion inhibition. For example,when approximately 5% phosphates are added to a solution containing 0.2%hypochlorite at pH 7.5, an 85% reduction in corrosion occurs. Whendimethyl lauryl amine oxide is then added to that combination, corrosionvirtually ceases. Some surface active agents are listed among corrosioninhibitors (Uhlig, H. H.: The Corrosion Handbook, New York, Wiley &Sons, 910-911). However, no previous report is known of potentiation ofcorrosion inhibition by a combination of phosphates and a surface activeagent added to a chlorine-based sterilizing system.

In order to avoid inactivation of the germicidal solution bycontaminants such as inorganic salts, organic material or incompatibledetergents, and assure thorough wetting of the instrument to besterilized, immersion in conditioning bath may be added to thesterilizing system. The conditioning bath consists of ample quantitiesof separate washing composition containing the same amine oxide as wellas agents to control corrosion and pH. Thus, all materials to besterilized would be preconditioned in a solution containing theconditioning composition. Transfer of small amounts of the conditioningsolution to the sterilizing solution will not counteract the efficacy ofthe latter.

Shelf-life requirements necessitate that the major components of thesterilizing solution (hypochlorite, phosphates and surfactant) remainseparate until mixed for use. To avoid errors in preparation, acompartmented bag was devised which assures complete mixing of allcomponents when the bag is opened. A colored indicator added to thecomponent in the center compartment acts as a safeguard. Alteration inthe central color of the package warns the user that leakage betweencompartments has occurred. The indicator color immediately disappearswhen combined with small quantities of hypochlorite. To complete thesterilizing solution, the three compartments in the package are added toa measured amount of water.

Bacteriological tests on a specific formulation of the sterilizationsystem, Solution O (see Examples V-VII) prove it to be a remarkablegermicide. High titres of vegetative organisms are killed withinminutes. The solution readily passed Great Britain's referee challenge,the "Kelsey-Sykes" test (Kelsey, J. C. & I. M. Maurer: An improved(1974) Kelsey-Sykes test for disinfectants. Pharm. J., Nov. 30, 1974).The sterilization system of the present invention can reliably passwithin 30 minutes the American "AOAC Sporicidal Test" which oftenrepresents the most difficult bacteriological hurdle. Although somedecay in available chlorine occurs during the 24 hours useful life ofthe solution, that change is insufficient to affect germicidal potency.A 24-hour old solution also passes the "AOAC Sporicidal Test".

Accordingly, an object of the present invention is to provide asterilization system which is efficacious as a sterilant, which isnon-corrosive and non-damaging, which has no deleterious effects oninstruments within the recommended contact time, has little tissueirritating properties, has good wetting capacity, and which is stablefor more than twenty-four hours.

Another object is to provide a reliable liquid sterilant system operablewithin a short enough cycle for practical application.

Another object is to provide a liquid sterilant of increased efficacy,reduced toxicity and prolonged life in which the potency does notrapidly deteriorate.

Another object is to provide a sterilization system which does notbecome contaminated by the materials being sterilized.

A further object is to provide a sterilization system which is so simplethat even untrained personnel can prepare and use it without significantchance of error.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view illustrating one embodiment of thesterilization system of the present invention.

FIG. 2 is an elevational view of the tri-pouch used in the sterilizationsystem of the present invention.

FIG. 3 is a sectional view taken along the lines 3--3 in FIG. 2.

FIG. 4 is a sectional view similar to FIG. 3 of an alternatearrangement.

FIG. 5 is a sectional view similar to FIG. 3 of a further alternatearrangement.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, FIG. 1 shows an overall view of oneembodiment of the sterilizing system of the present invention. Theillustrated sterilization system involves the use of two sealed plasticpouches 10 and 12. The entire contents of each pouch 10, 12 are mixedwith water in the containers 14, 16 respectively and the contents of thecontainers 14, 16 are then emptied into wide mouth containers or pans18, 20 respectively which define two baths in which the sterilizationprocess is performed as will be described.

In the illustrated embodiment, FIG. 2, the contents of the first pouch(10) used for the first bath contains cleaning and conditioning agents.The second pouch (12) for the second bath is a tri-pouch in that itconsists of three separate, sealed compartments 22, 24, 26 in which oneouter compartment (22 or 26) contains a hypochlorite solution, the otherouter compartment (22 or 26) contains a buffer and anticorrosive agent,and the intermediate compartment (24) sandwiched there between containsa surfactant or wetting agent preferably with a color indicator.

Turning to details of the illustrated embodiment, the tri-pouch (12) maybe made from four sheets of plastic film (31, 32, 33, 34,) which may besuperimposed one on top of the other and heat sealed together at theiredges (36) to form a pouch having the three separate compartments (22,24, 26). Each of the three separate compartments (22, 24, 26) iscompletely sealed from one another such that the three liquid componentswill be kept separate until the moment of use of the sterilizationsystem.

The sheets of plastic film (31-34) of the tri-pouch (12) may each bemade of a double thickness film as illustrated at 31a, 31b, 34a, 34brespectively in FIG. 3 to provide added integrity to prevent leakagethrough any pin holes which may occur during manufacture of singlethickness plastic film. The term double thickness may refer to what iscommercially known as co-extruded or laminated film.

The tri-pouch (12) has a portion with converging side seams to form atapered or funnel-like end portion (38) as shown in the drawings. Torelease the three liquid components from the tri-pouch (12), it is onlynecessary to snip off the pointed end of the tri-pouch (as indicated at40) with a pair of scissors or the like to simultaneously cut throughall three compartments. Accordingly, the liquid contents of all threecompartments (22, 24, 26) of the tri-pouch will pour out simultaneously,thereby mixing the three components and activating the sterilizationsystem. The contents of the tri-pouch (12) are emptied into thepreviously mentioned container (16) which contains water or to whichwater is added. Thereafter the contents of the container (16) is emptiedinto the pan (20) forming the second bath. The use of the tri-pouch (12)permits storage of the correct and premeasured amounts of the separatedliquid until ready for use.

As previously indicated, when it is desired to use the sterilizationsystem, the tapered end (34) of the tri-pouch (12) is merely snipped offand the three liquid ingredients will pour out simultaneously to mixduring the pouring operation. Thus, the use of the three compartmentpouch greatly reduces the chance of a partial mixing and virtuallyprevents use of less than all of all three of the components of thetri-pouch.

The arrangement of the tri-pouch also has the advantage that if eitherthe liquid sterilant or the buffer should leak internally, they wouldleak into center compartment (24) containing the wetting agent and thecolor indicator to effect a color change and thereby provide a visualindication that a leak has occurred. By way of example, the colorindicator may be chlorophenol red solution which gives the centercompartment (24) a reddish purple color. If the liquid sterilantsolution (e.g. hypochlorite) in one of the outer compartments, 22 or 26,were to leak into the center compartment (24), the chlorine/hypochloritewould oxidize the reddish purple color indicator and the package wouldappear as a pale straw yellow of the hypochlorite solution. Conversely,should the buffer and anticorrosive solution (e.g. phosphate) in theother of the outer compartments, 22 or 26, leak internally, it wouldcause a precipitate to occur in the center compartment (24). Thus, theabsence of the reddish purple color or the presence of the precipitatewould be an indication that an internal leak has occurred. The colorindicator is thereby able to provide a visual determination of whetheror not an internal leak has occurred at any time between the filling ofthe tri-pouch (12) to the time it is ready for use. Accordingly,assurance is readily provided to the user that no internal leakage hasoccurred and that the contents of the tri-pouch are safe to use.

The walls (31-34) of the tri-pouch (12) are made of a clear plastic filmso that the contents can be readily observed. By way of example, theplastic film may be polyethylene, polyethylene-ionomer coextrusion,polyethylene-polyamide laminate, or the like and may have a thickness offrom 0.002 in. to 0.020 in., preferably 0.006 in.

As an alternate arrangement, the membranes or septa of the tri-pouchcould be a double thickness such as indicated, for example, at 31c and31d in FIG. 5, with various color indicators interposed between the twothicknesses as indicated at 41, to provide further and easily detectedindication of a leak in one of the inner septa.

The pouch (10) containing the cleansing and conditioning agents may alsobe made of a clear plastic film and heat sealed around the edges (44).By way of example, the plastic film may be polyethylene,polyethylene-ionomer coextrusion, polyethylene-polyamide laminate, orthe like and may have a thickness of from 0.002 in. to 0.020 in.,preferably 0.006 in.

Returning to FIG. 1, when it is desired to sterilize, the first pouch(10), containing the cleaning and conditioning agent, is opened andemptied into the container (14). Tap water is then added to thecontainer (14) to bring the mixed contents to a given quantity ofsolution as may be indicated by marks on the container (14). Theresulting diluent is then poured into the pan (18) to provide a bath inwhich the various items to be sterilized may be conditioned prior toimmersion in the sterilizing solution.

Similarly, the tri-pouch (12) is snipped off at 40 by a pair of scissorsas previously described and all three liquid components simultaneouslyemptied into the container 16. As with the first pouch (10), thecontainer (16) is then filled with clear tap water to a mark which maybe provided on the container (16) and the resulting diluent subsequentlypoured into the second bath (20).

The items to be sterilized (44) are first immersed into the first pan(18) wherein such items are conditioned and then immersed into thesecond pan (20) where they are sterilized.

The purpose of the first bath containing the cleansing and conditioningagents is to clean the instruments to be sterilized by removing suchubiquitous organic contaminants as proteins or grease, to dilute andneutralize inorganic contaminants which otherwise might react with thesterilant, and to thoroughly wet the surfaces of the item to besterilized. This conditioning solution is utilized because the chlorinein the second bath readily combines with a wide variety of organic andinorganic substances and is thereby inactivated. Thus, the conditioningin the first bath (10) is performed with a cleaning agent which iscompatible with chlorine, a 12 carbon alkyldimethyl amine oxide, forexample, dimethyl lauryl amine oxide, which may be obtained, forexample, from Onyx Chemical Company, Division of Millmaster Onyx Corp.of Jersey City, N.J., under the name of "Ammonyx LO", and which is setforth in U.S. Pat. No. 3,296,145. Also contained in the first bath arepotassium pyrophosphate and tripotassium phosphate which serve tosaponify oily substances, sequester metallic ions, deflocculateparticles, act as anticorrosive agents, and aid in the pH control of thesolution. Pylam turquoise blue acts as a coloring agent and may beomitted or another coloring agent may be substituted.

An example of a specific composition in the first pouch (10) is:

7.5 g. potassium pyrophosphate

7.5 g. tripotassium phosphate

38 ml. dimethyl lauryl amine oxide (30% active)

0.0128 g. Pylam turquoise blue

60 ml. tap water

The first bath is readily prepared by mixing the contents of first pouch(10) with 3.3 liters of tap water to form 3.4 liters of solution. If theamounts are doubled, 6.8 liters of solution are obtained, etc.

The second aqueous bath in the pan (20) desirably comprises:

0.02 to 1% of an alkali metal or alkaline/earth metal hypochlorite

0.1 to 0.5% of a nonionic surfactant which is compatible with chlorineand phosphates (30% active)

1.4 to 20% of di (alkali metal) phosphate

titrated to a pH of 7.0 to 8.0 with mono (alkali metal) phosphate, withthe proviso that the lower limit of di (alkali metal) phosphate is 4.0%when the amount of said hypochlorite is from 0.5 to 1%, thesepercentages being based on the weight of the ingredient (in grams) per100 ml of solution. The amount of mono (alkali metal) phosphate requiredto obtain the indicated pH ranges from 0.08 to 21%. The use of 0.05 to0.3% of sodium hypochlorite, 0.2 to 0.4% of dimethyl lauryl amine oxide(30% active), 2 to 13% of dipotassium phosphate, titrated withmonopotassium phosphate to a pH from 7.2 to 7.7 are preferred. Theamount of monopotassium phosphate required to obtain the indicated pHranges from 0.33 to 9.66%.

As an example, to obtain the aforementioned second bath, one of theouter compartments, say outer compartment 22, of the tri-pouch suitablycontains 136 ml of 6% sodium hypochlorite.

The other outer compartment (26) suitably has the following contents:

314 ml. water

360 g. dipotassium phosphate

80 g. monopotassium phosphate

0.12 g. sodium chromate

The chromate is used as a colorant and can be replaced by othercolorants which do not react adversely with the chlorine. The chromatecan alternatively be added to the hypochlorite compartment or can beomitted.

The center compartment (24) of the tri-pouch (12) suitably has thefollowing contents:

14.1 ml. dimethyl lauryl amine oxide (30% active)

5.2 ml. 0.04% chlorophenol red solution

80.7 ml. water

If the color of the chlorophenol red disappears, this means that thesolution from at least one of the outer compartments has leaked into thecenter compartment (24). In this case, the affected tri-pouch should bediscarded. Colorants other than chlorophenol red can be used so long asthey do not adversely affect the final chlorine bath.

The second bath is readily prepared by mixing the contents of the sealedcompartments of the tri-pouch (12) with 3.3 liters of water to form 4liters of solution. If the amounts are doubled, 8 liters of solution areobtained, etc.

The recommended concentration of 0.2% hypochlorite provides an extremelygenerous safety margin. The solution is still fully effective when it is24 hours old though it contains about one-third less available chlorine.Generally, the solution will be effective for 48 to 72 hours.

The pH of the second bath preferably is 7.5 to provide minimum tissueirritancy, although it may vary from 7.0 to 8.0. In addition tocontrolling pH, the phosphates act as saponifiers and cleaning agents.

In operating the invention, the instruments to be sterilized may beimmersed into the first bath (18) for a period on the order of 2 minutesand then are transferred to the second bath where sterilization isaffected in 15-30 minutes. As previously indicated, transfer of smallamounts of the cleansing solution from the first bath to the second bathwill not counteract the efficacy of the sterilant.

As an indication of the uniqueness of a 12 carbon alkydimethyl amineoxide as a surfactant in the sterilizing compositions of this invention,the following surfactants were found to be incompatible with sodiumhypochlorite or hypochlorous acid:

    ______________________________________                                                   IONIC                                                              TRADEMARK  TYPE      DESCRIPTION                                              ______________________________________                                        Aerosol OS anionic   sodium isopropyl napthalene                                                   sulfonate                                                Advawet #33                                                                              nonionic  fatty acid ester glycol                                  Advawet #43                                                                              nonionic  fatty acid ester glycol                                  Ammonyx CDO                                                                              *nonionic coco amido propyl dimethyl                                                    amine oxide                                              Avirol 300 anionic   triethanolamine alkyl sulfate                            Avirol 116-E                                                                             anionic   sodium lauryl ether sulfate                              Chemadene 300                                                                            amphoteric                                                                              amine salt                                               Cerfak 1400                                                                              anionic   alkyl polyoxyethylene ether                              Cordon 300 anionic   sulfated oil                                             Detersol             pine oil detergent                                       T-Special                                                                     Emkapon TS anionic   amide sulfonate                                          Emkatex AA anionic   alkyl aryl sulfonate                                     Foamole AR nonionic  coconut oil alkanol amide                                Gafac RA-600                                                                             anionic   free acid of complex organic                                                  phosphate ester                                          Klearfac AA-250                                                                          anionic   free acid of organic phosphate                                                ester                                                    Lonzaine 12-C                                                                            amphoteric                                                                              coco alkyl amino betaine                                 Miranol JEM                                                                              amphoteric                                                                              dicarboxylic octoic sulfonated                                                amine                                                    Miranol JS amphoteric                                                                              carboxylated sulfonated amine of                                              octoic acid                                              Maprofix 60-S                                                                            anionic   sodium lauryl ether sulfate                              Merpol HC  nonionic  ETO condensate of long chain of                                               fatty alcohol                                            Monoflor 52                                                                              nonionic  fluorohydrocarbon                                        Nopcowet 50                                                                              anionic   sulfonated alkyl ester                                   Olapon ND-100                                                                            nonionic  polyethylene glycol ether of                                                  linear alcohol                                           Pleurafax A-38                                                                           nonionic  straight chain aliphatic oxy-                                                 alkylated alcohol                                        Pleuronic L-64                                                                           nonionic  ethylene oxide condensate                                Richonate TAB                                                                            anionic   triethanolamine dodecyl benzene                                               sulfonate                                                Richonate 45-B                                                                           anionic   sodium dodecyl benzene                                                        sulfonate                                                Rueterg 97-S                                                                             anionic   alkyl aryl sulfonate                                     Sellogen   anionic   methyl taurine condensate                                concentrate                                                                   Siponic L-4                                                                              nonionic  ethoxylated lauryl alcohol                               Standapol AB-45                                                                          amphoteric                                                                              alkyldimethyl betaine                                    Standapol ES-3                                                                           anionic   sodium lauryl ether (3 moles                                                  ETO) sulfate                                             Standapol  amphoteric                                                                              betaine                                                  OLB-50                                                                        Standamox 01                                                                             nonionic  oleyl dimethyl amine oxide                               Tamol SN   anionic   sodium napthalene sulfonate                              Triton X-114                                                                             nonionic  octyl phenoxypolyethoxyethanol                           Tween 20   nonionic  polyoxyethylene (20) sorbitan                                                 monolaurate                                              Tween 80   nonionic  polyoxyethylene (20) sorbitan                                                 monolaurate sodium amine                                                      phosphate                                                Wayhib S   anionic   sodium amine phosphate                                   Zonyl FSN  nonionic  fluorocarbon complex                                     Zonyl FSA  anionic   fluorohydrocarbon complex                                                     All cationic surfactants                                 ______________________________________                                         *nonionic above pH 7, cationic below pH 7                                

The following surfactants were found to be compatible with hypochloritesolutions but incompatible with the concentration of phosphate in testSolution Q (see Example V):

    ______________________________________                                                   IONIC                                                              TRADEMARK  TYPE     DESCRIPTION                                               ______________________________________                                        Abex 18-S  anionic                                                            Ammonyx MO nonionic*                                                          Ammonyx MCO                                                                              nonionic*                                                          Tetranol   anionic  sulfated fatty ester                                      Gemtex HC-70                                                                             anionic  sodium dihexyl sulfosuccinate                             Standapol ES-2                                                                           anionic  sodium lauryl ether (2 moles ETO)                                             sulfate                                                   Sipon LSB  anionic  sodium lauryl sulfate                                     Mersonol 840                                                                             anionic  sodium dihexyl sulfosuccinate                             Aerosol OT-100                                                                           anionic  sodium dioctyl sulfosuccinate                             Standapol WAQ                                                                            anionic  sodium lauryl sulfate                                     Triton X-301                                                                             anionic  sodium alkyl aryl polyether sulfate                       Carbanone BD                                                                             anionic  carboxylated polyethoxy of linear                                             alcohol                                                   Monoflor-31                                                                              anionic  fluorohydrocarbon complex                                 Aerosol CT                                                                    Triton X-200                                                                             anionic  sodium alkyl aryl polyether                                                   sulfonate                                                 Siponic E-2                                                                              nonionic ethoxylated (2 moles ETO) cetyl                                               stearyl alcohol                                           Steol CS-46                                                                              anionic  sodium coconut ether sulfate                              Petrowet R anionic  sodium hydrocarbon sulfonate                              Alkanol 189-S                                                                            anionic  sodium hydrocarbon sulfonate                              Victawet 35-B                                                                            anionic  polyphosphate of aliphatic group                          Victawet 58-B                                                                            anionic  phosphorated higher alcohol**                             ______________________________________                                         *nonionic above pH 7                                                          **cloudy when sodium hypochlorite is added   The uniqueness of phosphates     as corrosion inhibitors for use in hypochlorite solutions is indicated by     the following investigative results. The following corrosion inhibitors do     not completely inhibit the corrosion caused by hypochlorite solutions.

1. Sodium silicate is an alkaline salt. It raises the pH of the chlorinesolutions to 10.5. Lowering the pH causes the formation of insolublesilicic acid, which is very weak acid having a dissociation constant of2×10⁻¹⁰. Sodium silicate inhibits corrosion in its alkaline environment(Botham, G .H. & G. A. Dummet, Corrosion by commercial sodiumhypochlorites and its inhibition, J. Dairy Res., 16:23, 1949) but theundissociated silicic acid has no corrosion inhibiting propertiesbecause of its low solubility.

2. Sodium molybdate was found to reduce corrosion of sodium hypochloritesolutions at a pH of 7.5 to 8, but it did not completely eliminatecorrosion when tested up to a concentration of 10%. Sodium molybdatedoes not bind free chlorine.

3. Zinc ions form insoluble zinc hydroxide at pH 7.5 and, therefore, areof no use as a corrosion inhibitor for use in hypochlorite solutions.The dissociation constant for zinc hydroxide is 9.6×10⁻⁴ and it isinsoluble in water.

4. Sodium chromate was found to reduce corrosion of sodium hypochloritesolutions at pH of 7.5 to 8, but did not completely eliminate corrosionwhen tested up to a concentration of 1%. Sodium chromate is toxic inhigh concentrations.

5. Sodium sulfite is a reducing agent and will reduce Cl+ to Cl-.

6. Sodium nitrite is a reducing agent and will reduce to Cl+ to Cl-.

7. The surfactant, Chemadene 300 was found to eliminate corrosion whenused in high concentrations, but it was also found to bind freechlorine.

The following are exemplifications of various aspects of this invention.

EXAMPLE I

Controlling Corrosion of Metals in Sodium Hypochlorite Solutions clPURPOSE

The purpose of this experiment is to demonstrate the corrosioninhibiting effect of increasing concentrations of mono and dipotassiumphosphate in sodium hypochlorite solutions, with and without a nonionicsurface active agent.

MATERIALS

1. Sodium hypochlorite (Purex Bleach)

2. Monopotassium phosphate (KH2PO4)

3. Dipotassium phosphate (K2HPO4)

4. Dimethyl lauryl amine oxide (30% active)

5. Disposable carbon steel scalpel blades, #11 (Fisher Scientific Cat.#9-916-B)

TEST SOLUTIONS

A. 0.2% NaOCl--(pH 10.5)

B. 0.2% NaOCl, 0.35% amine oxide--(pH 10.5)

C. 0.2% NaOCl, 0.24% KH2PO4--(pH 7.5)

D. 0.2% NaOCl, 0.24% KH2PO4, 0.35% amine oxide--(pH 7.5)

E. 0.2% NAOCl, 0.43% KH2PO4, 0.5% K2PO4--(pH 7.5)

F. 0.2% NaOCl, 0.43%, KH2PO4, 0.5% K2HPO4, 0.35% amine oxide--(pH 7.5)

G. 0.2% NaOCl, 0.55% KH2PO4, 1% K2HPO4--(pH 7.5)

H. 0.2% NaOCl, 0.55% KH2PO4, 1% K2HPO4, 0.35% amine oxide--(pH 7.5)

I. 0.2% NaOCl, 0.75% KH2PO4, 2% K2HPO4--(pH 7.5)

J. 0.2% NaOCl, 0.75% KH2PO4, 2% K2HPO4, 0.35% amine oxide--(pH 7.5)

K. 0.2% NaOCl, 1.02% KH2PO4, 4% K2HPO4--(pH 7.5)

L. 0.2% NaOCl, 1.02% KH2PO4, 4% K2HPO4, 0.35% amine oxide--(pH 7.5)

M. 0.2% NaOCl, 1.18% KH2PO4, 6% K2HPO4--(pH 7.5)

N. 0.2% NaOCl, 1.28% KH2PO4, 6% K2HPO4, 0.35% amine oxide--(pH 7.5)

O. 0.2% NaOCl, 1.35% KH2PO4, 8% K2HPO4--(pH 7.5)

P. 0.2% NaOCl, 1.35% KH2PO4, 8% K2HPO4, 0.35% amine oxide--(pH 7.5)

PROCEDURE

Sixteen pairs of #11 surgical disposable carbon steel scalpel bladeswere accurately weighed on a micro balance. Each pair of blades was putinto a separate test solution and the blades were allowed to soak fortwo hours. At the end of the soaking period, any corrosion productsformed on the blades were washed off. The blades were then room airdried for one hour and each pair was reweighed on the micro balance. Theweight loss for each pair of blades was computed.

RESULTS

                  TABLE NO. 1                                                     ______________________________________                                        TEST                                %                                         SOLU-   INITIAL   FINAL     WEIGHT  WEIGHT                                    TIONS   WEIGHT    WEIGHT    LOSS    LOSS                                      ______________________________________                                        A       732.32 mg.                                                                              728.50 mg.                                                                              3.82 mg.                                                                              0.522%                                    B       740.49 mg.                                                                              737.31 mg.                                                                              3.18 mg.                                                                              0.429%                                    C       755.21 mg.                                                                              752.24 mg.                                                                              2.97 mg.                                                                              0.393%                                    D       758.10 mg.                                                                              756.12 mg.                                                                              1.98 mg.                                                                              0.261%                                    E       753.37 mg.                                                                              751.74 mg.                                                                              1.63 mg.                                                                              0.216%                                    F       750.60 mg.                                                                              749.30 mg.                                                                              1.30 mg.                                                                              0.173%                                    G       735.15 mg.                                                                              731.70 mg.                                                                              3.45 mg.                                                                              0.469%                                    H       740.09 mg.                                                                              738.12 mg.                                                                              1.97 mg.                                                                              0.266%                                    I       727.00 mg.                                                                              726.42 mg.                                                                              0.58 mg.                                                                              0.080%                                    J       753.91 mg.                                                                              753.81 mg.                                                                              0.10 mg.                                                                              0.013%                                    K       742.96 mg.                                                                              742.18 mg.                                                                              0.78 mg.                                                                              0.105%                                    L       750.93 mg.                                                                              750.92 mg.                                                                              0.01 mg.                                                                              0.001%                                    M       753.15 mg.                                                                              753.14 mg.                                                                              0.01 mg.                                                                              0.001%                                    N       752.18 mg.                                                                              752.18 mg.                                                                              0.00 mg.                                                                              0.000%                                    O       755.31 mg.                                                                              755.30 mg.                                                                              0.01 mg.                                                                              0.001%                                    P       735.65 mg.                                                                              735.65 mg.                                                                              0.00 mg.                                                                              0.000%                                    ______________________________________                                    

                  TABLE NO. 2                                                     ______________________________________                                                              %                                                       TEST     SCALPEL      CORROSION INHIBITION                                    SOLUTION WEIGHT LOSS  FROM "A"                                                ______________________________________                                        A        3.82 mg.     --                                                      B        3.18 mg.     16.8%                                                   C        2.97 mg.     22.3%                                                   D        1.98 mg.     48.2%                                                   E        1.63 mg.     57.3%                                                   F        1.30 mg.     66.0%                                                   G        3.45 mg.     9.7%                                                    H        1.97 mg.     48.4%                                                   I        0.58 mg.     84.8%                                                   J        0.10 mg.     97.4%                                                   K        0.78 mg.     79.6%                                                   L        0.01 mg.     99.7%                                                   M        0.01 mg.     99.7%                                                   N        0.00 mg.     100.0%                                                  O        0.01 mg.     99.7%                                                   P        0.00 mg.     100.0%                                                  ______________________________________                                    

CONCLUSION

A solution of 0.2% sodium hypochlorite in water was very corrosive tothe steel scalpel blades. The addition of the amine oxide to thehypochlorite reduced the corrosion by 16.8%.

Buffering the sodium hypochlorite solution to pH 7.5 with monopotassiumphosphate reduced the corrosion by 22.3%. The addition of amine oxidefurther reduced the corrosion of the buffered hypochlorite by 33.3%. Theamine oxide, therefore, reduced the corrosion twice as much in thebuffered hypochlorite than it did in the unbuffered hypochlorite.

The addition of increasing amounts of dipotassium phosphate to thesodium hypochlorite solution, and buffering the solution to a pH of 7.5with monopotassium phosphate, showed increasing corrosion inhibition(see Table No. 2). The addition of amine oxide showed greatly increasinginhibition with increasing concentrations of phosphate. Only thecombination of phosphates and amine oxide completely eliminated thecorrosion of the steel disposable scalpel blades caused by the sodiumhypochlorite.

EXAMPLE II

Controlling Corrosion of Metals in NaOCl Solution

PURPOSE

The purpose is to establish the inhibiting effect of increasingconcentrations of mono and dipotassium phosphate in sodium hypochloritesolutions, with and without a surface active agent.

MATERIALS

1.Sodium hypochlorite (Purex Bleach)

2. Monopotassium phosphate (KH2PO4)

3. Dipotassium phosphate (K2HPO4)

4. Dimethyl lauryl amine oxide (30active)

5. Disposable scalpel blades, #21 (Fisher Scientific Co. Cat. #8-918-B)

TEST SOLUTIONS

A 0.02& NaOCl (pH 10.05)

B 0.02% NaOCl, 0.35% amine oxide (pH 9.8)

C 0.02% NaOCl, 0.033% KH2PO4 (pH 7.5)

D 0.02% NaOCl, 0.033% KH2PO4, 0.35% amine oxide (pH 7.5)

E 0.02% NaOCl, 0.25% K2HPO4, 0.058% KH2PO4 (pH 7.5)

F 0.02% NaOCl, 0.25% K2PO4, 0.058% KH2PO4, 0.35% amine oxide (pH 7.5)

G 0.02% NaOCl, 0.5% K2HPO4, 0.117% KH2PO4 (pH 7.5)

H 0.02% NaOCl, 0.5% K2HPO4, 0.117% KH2PO4, 0.35% amine oxide (pH 7.5)

I 0.02% NaOCl, 1.0% K2HPO4, 0.192% KH2PO4 (pH 7.5)

J 0.02% NaOCl, 1.0% K2HPO4, 0.192% KH2PO4, 0.35% amine oxide (pH 7.5)

K 0.02% NaOCl, 2.0% K2HPO4, 0.433% KH2PO4 (pH 7.5)

L 0.02% NaOCl, 2.0% K2PO4, 0.433% KH2PO4, 0.35% amine oxide (pH 7.5)

PROCEDURE

Twelve pairs of #21 surgical disposable scalpel blades were accuratelyweighed on a micro balance. Each pair of blades was put into a separatetest solution and the blades were allowed to soak for two hours. At theend of the soaking period, any corrosion products formed on the bladeswere washed off. The blades were then room air dried for at least onehour and each pair was reweighed on the micro balance. The weight lossfor each pair of blades was computed. cl RESULTS

                  TABLE 5                                                         ______________________________________                                        Test   Initial   Final     Weight Visible                                     Solution                                                                             Weight    Weight    Loss   Observations                                ______________________________________                                        A'     2061.79 mg                                                                              2059.29 mg                                                                              2.50 mg                                                                              general rusting                             B'     2014.84 mg                                                                              2014.20 mg                                                                              0.64 mg                                                                              many small pits                                                               with rust                                   C'     2017.10 mg                                                                              2013.65 mg                                                                              3.45 mg                                                                              general rusting                                                               more than "A"                               D'     2004.59 mg                                                                              2002.98 mg                                                                              1.61 mg                                                                              pitting and streak                                                            rusting                                     E'     1975.16 mg                                                                              1973.37 mg                                                                              1.79 mg                                                                              colorful streak-                                                              like corrosion                              F'     1998.42 mg                                                                              1997.35 mg                                                                              1.07 mg                                                                              medium large pits,                                                            tarnishing                                  G'     1970.39 mg                                                                              1969.37 mg                                                                              1.02 mg                                                                              medium large pits,                                                            tarnishing                                  H'     1990.17 mg                                                                              1989.40 mg                                                                              0.77 mg                                                                              medium pits,                                                                  tarnished                                   I'     1998.35 mg                                                                              1997.64 mg                                                                              0.71 mg                                                                              small pits, some                                                              tarnishing                                  J'     2018.52 mg                                                                              2018.02 mg                                                                              0.50 mg                                                                              few small pits                              K'     2006.45 mg                                                                              2006.31 mg                                                                              0.14 mg                                                                              two very small                                                                pits                                        L'     1984.98 mg                                                                              1984.98 mg                                                                                0 mg no corrosion                                ______________________________________                                    

                  TABLE 6                                                         ______________________________________                                        Test   % Corrosion Inhibition                                                                         % Corrosion Inhibition                                Solution                                                                             Relative to "A'" Relative to "C'"                                      ______________________________________                                        A'     --               --                                                    B'     74.4%            --                                                    C'     -38.0%           --                                                    D'     35.6%            53.3%                                                 E'     28.4%            48.1%                                                 F'     57.2%            69.0%                                                 G'     59.2%            70.4%                                                 H'     69.2%            77.7%                                                 I'     71.6%            79.4%                                                 J'     80.0%            85.5%                                                 K'     94.4%            95.9%                                                 L'      100%             100%                                                 ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                                                      Comparison                                      Test   % Corrosion Inhibition Compared                                                                      Solution                                        Solution                                                                             To same solutions without Amine Oxide                                                                Code                                            ______________________________________                                        B'     74.4%                  A'                                              D'     53.3%                  C'                                              F'     40.2%                  E'                                              H'     24.5%                  G'                                              J'     29.6%                  I'                                              ______________________________________                                    

CONCLUSION

A solution of 0.02% sodium hypochlorite in water was very corrosive tothe steel scalpel blades. The addition of the amine oxide to thehypochlorite reduced the corrosion. Buffering the sodium hypochloritesolutions to pH 7.5 with monopotassium phosphate increased the corrosionby 38%. The addition of the amine oxide reduced corrosion of thebuffered hypochlorite by 53.3%. The addition of increasing amounts ofdipotassium phosphate to the sodium hypochlorite solution, and bufferingto a pH of 7.5 with monopotassium phosphate, provided increasingcorrosion inhibition. In each solution studied, greater corrosioninhibition was obtained when the amine oxide was included. Solution "L'"did not cause corrosion of the steel scalpel blades after a two hourexposure.

EXAMPLE III

Controlling corrosion of metals in NaOCl Solutions

PURPOSE

The purpose is to establish the minimum concentrations of phosphatesneeded to eliminate corrosion of surgical steel scalpel blades in a0.02% sodium hypochlorite solution at pH 7.5.

MATERIALS

1. Sodium hypochlorite (from Purex Bleach)

2. Monopotassium phosphate (KH2PO4)

3. Dipotassium phosphate (K2HPO4)

4. Dimethyl lauryl amine oxide (30% active)

5. Disposable scalpel blades, #21 (Fisher Scientific Co. Cat. (#8-918-B)

TEST SOLUTIONS

R. 0.02% NaOCl, 0.025% KH2PO4, 0.35% amine oxide

S. 0.02% NaOCl, 1% K2HPO4, 0.167% KH2PO4, 0.35% amine oxide

T. 0.02% NaOCl, 1.2% K2HPO4, 0.233% KH2PO4, 0.35% amine oxide

U. 0.02% NAOCl, 1.4% K2HPO4, 0.267% KH2PO4, 0.35% amine oxide

V. 0.02% NaOCl, 1.6% K2HPO4, 0.33% KH2PO4, 0.35% amine oxide

W. 0.02% NaOCl, 1.8% K2HPO4, 0.35% KH2PO4, 0.35% amine oxide

X. 0.02% NaOCl, 2.0% K2HPO4, 0.400% amine oxide

Z. 0.02% NaOCl, 2.2% K2HPO4, 0.433% KH2PO4, 0.35% amine oxide

PROCEDURE

Eight pairs of surgical disposable scalpel blades were accuratelyweighed on a Satorius Microbalance. Each pair of blades was put into aseparate test solution and the blades were allowed to soak for fourhours. At the end of the soaking period, the blades were removed fromthe solutions and any corrosion products formed on the blades werewashed off. The blades were then dried at room temperature for at leastone hour and then reweighed. The weight loss for each pair of blades wascomputed.

RESULTS

                  TABLE 3                                                         ______________________________________                                        Test                                                                          Solu-                                                                              Initial   Final     Weight Visible                                       tion Weight    Weight    Loss   Observations                                  ______________________________________                                        R.   2018.69 mg                                                                              2016.20 mg                                                                              2.49 mg                                                                              much corrosion                                S.   2002.82 mg                                                                              2002.65 mg                                                                              0.17 mg                                                                              few pits                                      T.   2009.89 mg                                                                              2009.82 mg                                                                              0.07 mg                                                                              two visible pits                              U.   1984.31 mg                                                                              1984.29 mg                                                                              0.02 mg                                                                              no visible corrosion                          V.   1974.62 mg                                                                              1974.60 mg                                                                              0.02 mg                                                                              no visible corrosion                          W.   1982.88 mg                                                                              1982.87 mg                                                                              0.01 mg                                                                              no visible corrosion                          X.   2013.87 mg                                                                              2013.87 mg                                                                                0 mg no visible corrosion                          Z.   1967.18 mg                                                                              1967.17 mg                                                                              0.01 mg                                                                              no visible corrosion                          ______________________________________                                    

                  TABLE 4                                                         ______________________________________                                        TEST     % INHIBITION OF CORROSION RELATIVE                                   SOLUTION TO TEST SOLUTION "R"                                                 ______________________________________                                        S.       93.2%                                                                T.       97.2%                                                                U.       99.2%                                                                V.       99.2%                                                                W.       99.6%                                                                X.        100%                                                                Z.       99.6%                                                                ______________________________________                                    

CONCLUSION

No detectable corrosion was found in Solutions "U" through "Y".

A 93 to 97% reduction in corrosion occurred in solutions "S" and "T".

EXAMPLE IV

Controlling Corrosion in NaOCl Solutions

PURPOSE

The purpose of this experiment is to establish the minimum concentrationof phosphates needed to eliminate corrosion of surgical steel scalpelblades in a 0.5% sodium hypochlorite solution at pH 7.5.

MATERIALS

1. Sodium hypochlorite (from Purex Bleach)

2. Monopotassium phosphates (KH2PO4)

3. Dipotassium phosphate (K2HPO4)

4. Dimethyl lauryl amine oxide

5. Disposable scalpel blades, #21 (Fisher Scientific Co. Cat. #8-918-B)

TEST SOLUTIONS

M' 0.5% NaOCl, 0.35% amine oxide, 0.500% KH2PO4

N' 0.5% NaOCl, 0.35% amine oxide, 1% K2HPO4, 0.633% KH2PO4

O' 0.5% NaOCl, 0.35% amine oxide, 2% K2HPO4, 0.967% KH2PO4

P' 0.5% NaOCl, 0.35% amine oxide, 4% K2HPO4, 1.40% KH2PO4

R' 0.5% NaOCl, 0.35% amine oxide, 6% K2HPO4, 2.00% KH2PO4*

S' 0.5% NaOCl, 0.35% amine oxide, 8% K2HPO4, 2.53% KH2PO4**

T' 0.5% NaOCl, 0.35% amine oxide, 10% K2HPO4, 3.48% KH2PO4***

U' 0.5% NaOCl, 0.35% amine oxide, 12% K2HPO4, 3.77% KH2PO4****

V' 0.5% NaOCl, 0.35% amine oxide, 14% K2HPO4, 4.13% KH2PO4*****

W' 0.5% NaOCl, 0.35% amine oxide, 16% K2HPO4, 4.90% KH2PO4******

PROCEDURE

Ten pairs of surgical disposable scalpel blades were accurately weighedon a Sartorius Microbalance. Each pair of blades was immersed inseparate test solutions and allowed to soak for two hours. At the end ofthe soaking period, the blades were removed from the test solutions andany corrosion products were washed off. The blades were then room airdried for at least one hour and then reweighed. The weight loss for eachpair of blades was computed.

RESULTS

                  TABLE 1                                                         ______________________________________                                        Test                                                                          Solu-                                                                              Initial   Final     Weight Visible                                       tion Weight    Weight    Loss   Observations                                  ______________________________________                                        M'   2043.15 mg                                                                              2033.52 mg                                                                              9.63 mg                                                                              gross corrosion                               N'   2033.28 mg                                                                              2022.29 mg                                                                              10.99 mg                                                                             gross corrosion (worse                                                        than "M")                                     O'   2024.60 mg                                                                              2018.04 mg                                                                              6.56 mg                                                                              many large pits                               P'   2016.91 mg                                                                              2016.81 mg                                                                              0.10 mg                                                                              few very small pits                           R'   2022.33 mg                                                                              2022.25 mg                                                                              0.08 mg                                                                              very few very small                                                           pits                                          S'   2034.16 mg                                                                              2034.10 mg                                                                              0.06 mg                                                                              3 or 4 tiny pits                              T'   2016.97 mg                                                                              2016.97 mg                                                                                0 mg no visible corrosion                          U'   1993.69 mg                                                                              1993.69 mg                                                                                0 mg no visible corrosion                          V'   1985.00 mg                                                                              1985.00 mg                                                                                0 mg no visible corrosion                          W'   2000.89 mg                                                                              2000.89 mg                                                                                0 mg no visible corrosion                          ______________________________________                                    

                  TABLE 9                                                         ______________________________________                                                                  % CORROSION                                                  TOTAL %          INHIBITION COM-                                     TEST     PHOSPHATES AS    PARED TO TEST                                       SOLUTION H2PO4 AND HPO4   SOLUTION "M'"                                       ______________________________________                                        M'       0.390%           --                                                  N'       1.04%            -14.1%                                              O'       1.86%            31.9%                                               P'       3.29%            99.0%                                               R'       4.86%            99.2%                                               S'       6.38%            99.4%                                               T'       8.22%            100%                                                U'       9.55%            100%                                                V'       10.93%           100%                                                W'       12.63%           100%                                                ______________________________________                                    

CONCLUSION

Complete corrosion inhibition of surgical steel scalpel blades in 0.5%sodium hypochlorite was obtained by the addition of 6.38% (and greater)total phosphates as H2PO4 and HPO4.

EXAMPLE V

Sterilization Testing of Test Solution Q

PURPOSE

To demonstrate that a one day old test solution can sterilize onemillion spores of Bacillus subtilis var. globigii inoculated from a hardwater suspension onto aluminum foil carriers.

MATERIALS

1. Test Solution Q--activated with hard water

0.2% sodium hypochlorite

0.35% dimethyl lauryl amine oxide (30% active)

9% dipotassium phosphate

2% monopotassium phosphate

2. Bacillus subtilis var. globigii spores in ethanol

3. Aluminum foil strips

4. Culture broth--formula in grams per liter

5 gm peptone

3 gm beef extract

3 gm yeast extract

2 gm dextrose

3 gm sodium sulfite

3 gm ammonium sulfate

10 ml Tween 80

0.7 gm lecithin

5. Hard water--0.304 gm CaCl2+0.14 gm MgCl2 6 H2O/Liter

METHOD

1. A quantity of spores in ethanol was centrifuged at 3000 rpm for 20minutes and the ethanol was decanted. The spores were resuspended insufficient sterile hard water so that the spore count was approximately2,000,000 spores per 0.05 ml. of inoculum.

2. Each of 25 aluminum foil carriers was inoculated with 0.05 ml of thespore/hard water suspension. The inoculum was allowed to dry onto thecarriers at room temperature for five days.

3. Twenty inoculated and dried carriers were immersed in a one day oldTest Solution Q. The carriers were removed after 15 minutes of exposureand aseptically transferred to individual tubes of culture broth. Allcultures were incubated for seven days at 37° C.

4. 0.2 ml of Test Solution Q was added to a tube of culture broth. Oneinoculated and dried carrier was added to the culture tube and incubatedat 37° C. The purpose of this test was to determine if there was anygrowth inhibitory effect of the solution on the germinating spores.

5. One tube of culture broth was incubated with an inoculated carrier toserve as a positive control.

6. The number of viable spores on a carrier was determined by washingthe spores off of the carrier with an ultrasonic cleaner into a 0.5%Tween 80 solution, and counting the spores in solution by thedilution/agar pour plate method.

RESULTS

Viable spore count--1,500,000 spores per carrier

Positive control--growth of Bacillus globigii

Inhibition control--growth of Bacillus globigii

Carriers exposed to Test Solution Q--no growth of Bacillus globigii inany of the 20 cultures.

CONCLUSION

No growth of Bacillus subtilis var. globigii occurred in any of thetwenty tubes of culture broth incubated with aluminum foil carriersexposed to a one day old Test Solution Q for 15 minutes. The growth ofBacillus globigii which occurred in the culture tube inoculated with 0.2ml of Test Solution Q and incubated with an inoculated carrier,demonstrated that all of the solution capable of exerting a growthinhibiting effect on the germinating spores had been effectivelyneutralized by the culture broth.

It is therefore concluded that all twenty aluminum foil carriersinoculated with a hard water suspension of Bacillus subtilis var.globigii were successfully sterilized by Test Solution Q using a 15minute exposure time.

EXAMPLE VI

Disinfection of Salmonella with Test Solution Q

PURPOSE

To demonstrate that a two day old Test Solution Q can disinfectSalmonella choleraesuis, inoculated from a hard water suspension ontostainless steel penicylinders, using a one minute exposure time.

MATERIALS

1. Test Solution Q--activated using hard water

2. Salmonella choleraesuis A.T.C.C. #10708

3. Stainless steel penicylinders (Fisher Cat. #7-907-5)

4. 0.1% Asparagine (Bacto)

5. Nutrient broth--formula in grams per liter

10 gm peptic digest of animal tissue

5 gm beef extract

5 gm sodium chloride

6. Culture broth--formula in grams per liter

5 gm peptone

3 gm beef extract

3 gm yeast extract

2 gm dextrose

3 gm sodium sulfite

3 gm ammonium sulfate

10 ml Tween 80

0.7 gm Lecithin

7. Hard water--formula in grams per liter

0.304 gm Calcium chloride

0.139 gm Magnesium chloride hexahydrate

METHOD

1. 65 stainless steel penicylinders were washed in 1 m NaCH and rinsedthoroughly. The washed penicylinders were placed in a flask, coveredwith 0.1% Asparagine, and autoclaved for 15 minutes at 121 degrees C.

2. The contents of six tubes, each containing 10 ml of a 48 hournutrient broth culture of Salmonella choleraesuis, were asepticallypoured into sterile centrifuge tubes. The culture was centrifuged at3000 rpm for 15 minutes and the supernatant liquid was decanted. Themicroorganisms were resuspended in 60 ml of sterile hard water.

3. The penicylinders were aseptically transferred to the hard waterbacterial suspension and were allowed to soak in the suspension for 15minutes. The penicylinders were then removed and placed vertically in asterile petri dish matted with two sterile circles of filter paper. Theinoculated penicylinder were dried in an incubator at 37 degrees C. for25-35 minutes.

4. Sixty inoculated and dried penicylinders were soaked in a two day oldTest Solution Q for 1 minute and transferred to individual tubes ofculture broth. All cultures were incubated at 37 degrees C. for 3 days.

5. One penicylinder, unexposed to Test Solution Q, was placed in aculture broth tube and incubated to serve as a positive control.

6. 0.2 ml of Test Solution Q was added to a tube of culture broth. Onepenicylinder was then placed in the broth and incubated. This testserved to detect unneutralized chlorine that might inhibit growth ofmicroorganisms.

7. One inoculated and dried penicylinder was shaken in 9.0 ml of sterilesaline for three minutes. The number of viable microorganisms in theresulting solution was determined by the dilution/agar pour platemethod.

RESULTS

Viable microorganisms on a penicylinder=300,000

Positive control--positive growth of Salmonella

Inhibition control--positive growth of Salmonella

60 penicylinders exposed Test Solution Q for one minute--

No growth of Salmonella in 59 cultures

Growth of Salmonella occurred in 1 culture

CONCLUSION

Growth of Salmonella choleraesuis occurred in only one of the sixtytubes containing penicylinders exposed to Test Solution Q. No inhibitionwas noted due to unneutralized solution. It is therefore concluded that59 of the 60 stainless steel penicylinders, inoculated with 300,000organisms of Salmonella choleraesuis in a hard water suspension, weresuccessfully sterilozied by Test Solution Q using a one minute exposure.

EXAMPLE VII

Kelsey-Sykes "Clean" Disinfectant Test using Test Solution Q

MATERIALS

1. Test Solution Q

2. Test Organisms

a. Staphylococcus aureus A.T.C.C. #6538

b. Pseudomonas aeruginosa A.T.C.C. #15542

c. Pseudomonas aeruginosa A.T.C.C. #27835

d. Escherichia coli A.T.C.C. #25922

e. Salmonella choleraesuis A.T.C.C. #10708

f. Klebsiella pneumoniae A.T.C.C. #13883

3. Medium for growth of test organisms--Bacto Synthetic Broth AOAC CodeNo. 0352 to which 0.1 ml of 10% dextrose has been added per 10 ml tubeof broth.

4. Recovery Broth--Nutrient broth (BBL) containing 3% Tween 80 (10 mlper tube)

5. Standard Hard Water--0.304 gm CaCl2, 0.139 gm MgCl2 6H2O/liter

METHOD

1. The Test Solution Q was diluted and activated by adding 3 parts ofstandard hard water to one part of Test Solution Q concentrate. Thefollowing test was performed using each of the microorganisms cited in"Materials", on a one day and a two day old Activated Test Solution Q.

2. Daily subcultures of each test organism were grown in 10 mlquantities of Synthetic broth. The subcultures were incubated for 24hours at 37 degrees C. Daily subcultures were made for at least fivedays but less than fourteen days.

3. A 24 hour subculture of each test organism was centrifuged at 3,000rpm for 15 minutes and the supernatant liquid was removed. Each testorganism was resuspended in 10 of sterile standard hard water and shakenfor one minute with a few glass beads. The 10 ml water/organismsuspension of each test organism was used as the inoculum for the test.

4. The following procedure was used for each test organism.

5. Three ml of Activated Test Solution Q were pipetted into a 50 mluncovered glass beaker. One ml of test inoculum was added to the TestSolution Q and the contents were mixed. Thirty seconds after theaddition, 0.02 ml of the Test Solution Q/inoculum mixture was added toeach of five recovery broths.

6. Ten minutes after the first addition, a second one ml inoculum wasadded to the Test Solution Q mixture and the contents were shaken.Thirty seconds after the second addition, 0.02 ml of the Test Solution Qmixture was added to each of five recovery broths.

7. Twenty minutes after the first addition, a third one ml inoculum wasadded to the Test Solution Q mixture and the contents were shaken.Thirty seconds after the third addition, 0.02 ml of the Test Solution Qmixture was added to each of five recovery broths.

8. All inoculated recovery broths were incubated at 37 degrees C. for 48hours.

9. A microorganism count was performed on each test organism inoculum bydilution in sterile water and preparation of agar pour plates of eachdilution. Colonies were counted after 2 days incubation at 37 degrees C.

10. All recovery broths showing no growth after 2 days of incubationwere inoculated with a 1:1000 dilution of test organism culture andreincubated for an additional 1 day. This test served to show thepresence of any inhibitory substance transferred to the recovery brothtubes. Positive growth indicates no inhibition.

RESULTS

Culture Codes: +=positive growth 0--no growth

    ______________________________________                                        Test So-            Recovery Broths                                           lution C                                                                             Test Organism                                                                             Count/ml (1)   (2)   (3)                                   ______________________________________                                        1 day  Staph       5.6 × 10.sup.8                                                                   00000 00000 00000                                        Pseudomonas 3.5 × 10.sup.9                                                                   00000 00000 00000                                        15542                                                                         Pseudomonas 9.8 × 10.sup.8                                                                   00000 00000 00000                                        27835                                                                         E. coli     5.5 × 10.sup.8                                                                   00000 00000 00000                                        Salmonella  1.0 × 10.sup.9                                                                   00000 00000 00000                                        Klebsiella  3.0 × 10.sup.9                                                                   00000 00000 00000                                 Inhibitory Test - all recovery broth tubes positive                           2 days Staph       3.5 × 10.sup.8                                                                   00000 00000 00000                                        Pseudomonas 5.6 × 10.sup.8                                                                   00000 00000 00000                                        15542                                                                         Pseudomonas 8.7 × 10.sup.8                                                                   00000 00000 00000                                        27835                                                                         E. coli     4.3 × 10.sup.8                                                                   00000 00000 00000                                        Salmonella  7.4 × 10.sup.8                                                                   00000 00000 00000                                        Klebsiella  1.2 × 10.sup.9                                                                   00000 00000 00000                                 Inhibitory Test - all recovery broth tubes positive                           ______________________________________                                    

CONCLUSION

Both a one day and a two day old Test Solution Q passed the Kelsey-SykesDisinfectant test under "clean" conditions using a 30 second exposuretime.

EXAMPLE VIII

The effect of the concentration of dimethyl lauryl amine oxide or silksuture loop sinking time

PURPOSE

To determine the optimal concentration of dimethyl lauryl amine oxidenecessary to rapidly eliminate air bubbles from standard A.O.A.C. stylesilk suture loops and cause them to sink in an aqueous solution.

MATERIALS

1. Dimethyl lauryl amine oxide (30% active)

2. Tap water

3. Silk suture loops (prepared according to the A.O.A.C. specifications)

4. Stop watch

5. Beakers

PROCEDURE

1. Concentrations of 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4 and 0.5% ofamine oxide in tap water were prepared.

2. A suture loop sinking time test was performed on each solution. Astop watch was used to determine the interval between the time a sutureloop was submerged in a test solution and the time at which the loopreached the bottom of the beaker.

3. At least four suture loops were tested in each solution. The averageof all the test times for each solution was determined.

RESULTS

    ______________________________________                                        (Average of 4 or more tests per solution)                                     Concentration of Amine Oxide                                                                   Average Sinking Time (seconds)                               ______________________________________                                        0.10%            62                                                           0.15             23                                                           0.20             17                                                           0.25             19                                                           0.30             13                                                           0.35             11                                                           0.40             10                                                           0.50             7                                                            ______________________________________                                    

CONCLUSION

A rapid decrease in sinking time occurred when the concentration ofamine oxide was increased from 0.1 to 0.2%. Above 0.3%, smalleradditional decreases in sinking times were noted.

EXAMPLE IX

Eye Irritation Testing of Test Solution Q

PURPOSE

The purpose of this test was to determine if Test Solution Q isirritating to the eye when tested on rabbits using the method describedby Dr. J. H. Draize.

MATERIALS 1. Three healthy New Zealand white rabbits

2. Test Solution Q

PROCEDURE

1. One tenth milliliter of freshly mixed Test Solution Q was instilledin the conjunctival sac of one eye in each of the three rabbits, withthe other eye of each rabbit serving as the control. The treated eyeswere not washed. Ocular reactions read at 24 and 48 hours.

2. Six days after the first treatment, two separate hourly conjunctivalinstillations of one tenth milliliter of freshly mixed Test Solution Qwere performed using the same test eyes as in the first treatment.Again, the treated eyes were not washed. Ocular reactions were read at24 and 48 hours.

3. Two days after the second treatment, three separate hourlyconjunctival instillations of one tenth milliliter of freshly mixed TestSolution Q were performed using the same test eyes as in the firsttreatment. Again, the treated eyes were not washed. Ocular reactionswere read at 24 and 48 hours.

4. Reactions were scored using the method suggested by Dr. Draize.

CONCLUSION

On the basis of the data presented herein, Test Solution Q is not anirritant to the rabbit eye when tested according to the method suggestedby Dr. J. H. Draize and described in "Appraisal of the safety ofChemicals in Food, Drugs and Cosmetics", published by the Association ofFood and Drug Officials of the United States.

    ______________________________________                                        Rabbits #1 and #3  First, Second and Third Treatment Results                           Days After Instillation:                                                                    1        2                                             ______________________________________                                        I. Cornea                                                                     A. Opacity-Degree of Density (area which)                                     is most dense is taken for reading)                                           Scattered or diffuse area-details of iris                                     clearly visible (1)    0        0                                             B. Area of Cornea Involved                                                    One quarter (or less) out not zero (1)                                                               0        0                                             Score equals A × B × 5                                                                   0 × 0 × 5 = 0                              Total maximum = 80                                                            II. Iris                                                                      A. Values                                                                     Folds above normal, congestion, swelling,                                     circumcorneal injection (any one or all of                                    these or combination of any thereof),                                         iris still reacting to light                                                  (sluggish reaction if positive) (1)                                                                  0        0                                             Score equals A × 5                                                                             0 × 5 = 0                                        Total possible maximum = 10                                                   III. Conjunctivae                                                             A. Redness (refers to palpebral                                               conjunctivae only)                                                            Vessels definitely injected above normal (1)                                                         0        0                                             B. Chemosis                                                                   Any swelling above normal                                                     (includes nictitating membrane) (1)                                                                  0        0                                             C. Discharge                                                                  Any amount different from normal                                              (does not include small                                                       amount observed in inner                                                      canthus of normal animals) (1)                                                                       0        0                                             Score (A + B + C) × 2                                                                          (0 + 0 + 0) × 2 = 0                              Total maximum +20                                                             ______________________________________                                    

    ______________________________________                                        Rabbit #2  First and Second Treatment Results                                          Days After Instillation:                                                                    1        2                                             ______________________________________                                        I. Cornea                                                                     A. Opacity-Degree of Density (area which                                      is most dense is taken for reading)                                           Scattered or diffuse area-details of iris                                     clearly visible (1)    0        0                                             B. Area of Cornea Involved                                                    One quarter (or less) but not zero (1)                                                               0        0                                             Score equals A × B × 5                                                                   × 0 × 5 = 0                                Total maximum = 80                                                            II. Iris                                                                      A. Values                                                                     Folds above normal, congestion, swelling,                                     circumcorneal injection (any one or all of                                    these or combination of any thereof),                                         iris still reacting to light                                                  (sluggish reaction if positive) (1)                                                                  0        0                                             Score equals A × 5                                                                             0 × 5 = 0                                        Total possible maximum =10                                                    III. Conjunctivae                                                             A. Redness (refers to palpebral                                               conjunctive only)                                                             Vessels definitely injected above normal (1)                                                         0        0                                             B. Chemosis                                                                   Any swelling above normal                                                     (includes nictitating membrane) (1)                                                                  0        0                                             C. Discharge                                                                  Any amount different from normal                                              (does not include small                                                       amount observed in inner                                                      canthus of normal animals) (1)                                                                       0        0                                             Score (A + B + C) ×  2                                                                         (0 + 0 + 0) × 2 = 0                              Total maximum =20                                                             ______________________________________                                    

    ______________________________________                                        Rabbit #2  Third Treatment Results                                                     Days After Instillation:                                                                    1        2                                             ______________________________________                                        I. Cornea                                                                     A. Opacity-Degree of Density (area which                                      is most dense is taken for reading)                                           Scattered or diffuse are-details of iris                                      clearly visible (1)    0        0                                             B. Area of Cornea Involved                                                    One quarter (or less) but not zero (1)                                                               0        0                                             Score equals A × P × 5                                                                   0 × 0 × 5 = 0                              Total maximum = 80                                                            II. Tris                                                                      A. Values                                                                     Folds above normal, congestion, swelling,                                     circumcorneal injection (any one or all of                                    these or combination of any thereof), iris                                    still reacting to light (sluggish reaction if                                 positive) (1)          0        0                                             Score equals A × 5                                                                             0 × 5 = 0                                        Total possible maximum =10                                                    III. Conjuctivae                                                              A. Redness (refers to palpebral conjunctivae                                  only) Vessels definitely injected above                                       normal (1)             0        0                                             B. Chemosis                                                                   Any swelling above normal (includes                                           nictitating membrane) (1)                                                                            0        0                                             C. Discharge                                                                  Any amount different from normal                                              (does not include small amount                                                observed in inner canthus of normal                                           animals). (1)          1        0                                             Score (A + B +  C) × 2                                                                         (1 + 0 + 0) × 2 = 2                              Total maximum =20                                                             ______________________________________                                    

The multi-compartment pouch of this invention can be used for purposesother than an instrument sterilizing solution. For example, it may beused in conjunction with an antimicrobial agent. Thus, it is effectivefor storing other germicidal solutions, such as disinfectants for bodilytissues, the ingredients of which must be kept separated until mixed foruse. Further, it is to be understood that the location of the solutionin the compartments can be varied and be within the scope of thisinvention. For example, the phosphate solution could be put in themiddle compartment with a color indicator which disappears when contactwith the hypochlorite occurs. As desired, the coloring agents may beomitted or substituted by other agents which are nonreactive to theother ingredients, in as much as the coloring agent is merely atell-tale device. Also, any number of plurality of compartments may beutilized.

It will be understood that utilizing the first bath with theconditioning agents is not always essential, because the secondchlorine-based sterilizing liquid bath, used alone, can still performits function with its effectiveness being a matter of degree dependingon the condition of the items being sterilized and their need forpre-conditioning treatment.

Although dimethyl lauryl amine oxide has been indicated as 30% activebecause of its commercial availability, other concentrations may beutilized and the amounts proportioned accordingly.

It is to be understood that the multi-compartment pouch of thisinvention, prior to filling with liquid components and complete sealing,is in and of itself an article of commerce. Thus, the multi-compartmentpouch may be initially made with filling openings for each compartmentand subsequently sealed after being filled with the desired contents.For example, three of the side seams may be initially sealed beforefilling, and the final and fourth side seams sealed after filling.Pouches with other than four side seams may also be used.

What is claimed is:
 1. A package for components for a mixture of thetype in which the components are to remain separate until mixed for use,comprising a plurality of layers of superimposed plastic film heatsealed at their edge portion to define a plurality of compartments eachsealed from one another, and color indicator means in at least one ofsaid compartments which when mixed with at least one of the componentsin another compartment effects a color change of at least one of saidcomponents to thereby provide visual indication of an internal leakbetween compartments before the package is opened, thereby providing avisual integrity check at the time the packaging is about to be used. 2.A package according to claim 1, wherein said plastic film has heatsealed lower edge portions which converge toward one another to form afunnel-like lower end portion on said package such that cutting throughsaid funnel-like lower end through all of said superimposed layers ofplastic film simultaneously opens all of said compartments so that thecomponents in each compartment simultaneously flow out from the packageand mix with one another to thereby activate said mixture.
 3. A safetyand mixing package for components of a sterilizing solution used forsterilizing medical articles and of the type in which the components areto remain separate until mixed and activated for use, comprising aplurality of layers of superimposed plastic film heat sealed at theiredge portion to define a plurality of compartments each sealed from oneanother, said plastic film having heat sealed lower edges with at leastportions thereof converging toward one another to form a funnel-likelower end on said package such that cutting of said funnel-like lowerend through all of said superimposed layers of plastic filmsimultaneously opens all of said compartments so that the components ineach compartment simultaneously flow out from the package and mix withone another to thereby activate said sterilizing solution, and colorindicator means in at least one of said compartments which when mixedwith at least one of the components in another compartment effects acolor change of at least one of said components to thereby providevisual indication of any internal leak between compartments before thepackage is opened, thereby providing a safety and visual integrity checkat the time the packaging is to be used and precluding inadvertent useof a defective sterilizing solution.
 4. A safety and mixing packageaccording to claim 3, wherein there is a center compartment and twoouter compartments, said color indicator means being disposed in saidcenter compartment such that any leakage between either outercompartment and said center compartment will effect said color change.5. A safety and mixing package according to claim 3, wherein one of saidcompartments contains a chlorine solution, a second contains phosphate,and a third contains a nonionic surfactant, said color indicator meanscomprises a colorant added to at least one of said components.
 6. Asafety and mixing package according to claim 5, wherein said colorindicator is selected from the group consisting of chlorophenol red andsodium chromate.
 7. A package for components of a mixture of the type inwhich the components are to remain separate until mixed for usecomprising a plurality of layers of superimposed plastic film heatsealed at their edge portion to define a plurality of compartments eachsealed from one another, each of said compartments containing at leastone of the components of said mixture, at least two of said compartmentsbeing separated by a double wall thickness of plastic film such that thedouble wall film defines a closed chamber therebetween, and colorindicator means in said closed chamber which when mixed with at leastone of the components in a juxtaposed compartment effects a color changeto thereby provide visual indication that a lead has occurred, therebyproviding a visual integrity check at the time the packaging is about tobe used.
 8. A package according to claim 7 further comprising a doublewall thickness of plastic film at the external face of an outsidecompartment of said package to define an external closed chamber, andcolor indicator means in said external closed chamber.